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View Full Version : Anybody uses or used Sandy King's Pyro Uno?



MDR
19-Feb-2014, 09:22
I wanted to try PYRO UNO and was looking for image examples as well as additional info regarding dev. times, successes and fails as well as overall look and feel.

The reason for trying Pyro Uno instead of Jay's 510-pyro is the phenidone which I can't get from my local chemist.

Thank you in advance

Dominik

sanking
19-Feb-2014, 10:36
I wanted to try PYRO UNO and was looking for image examples as well as additional info regarding dev. times, successes and fails as well as overall look and feel.

The reason for trying Pyro Uno instead of Jay's 510-pyro is the phenidone which I can't get from my local chemist.

Thank you in advance

Dominik

What film do you want to use it with? When I was working with Pyro Uno I ran BTZS tests with a few films and could provide you with the data if you are using the same film.

Sandy

MDR
19-Feb-2014, 12:27
Sandy thank you for your quick response. The films I want to use are Ilford FP4+and Hp5+ as well as Kodak T-max 100 and the odd Efke 100 and Fomapan 100 the latter two were made in non standard sizes so pretty much the only choices for 10x15cm film. Have you had time do to do some more research since 2008 or do you consider Pyro Uno a one time experiment. Thanks again
Dominik

sanking
19-Feb-2014, 18:35
Sandy thank you for your quick response. The films I want to use are Ilford FP4+and Hp5+ as well as Kodak T-max 100 and the odd Efke 100 and Fomapan 100 the latter two were made in non standard sizes so pretty much the only choices for 10x15cm film. Have you had time do to do some more research since 2008 or do you consider Pyro Uno a one time experiment. Thanks again
Dominik

Dominik,

I worked with the Pyro Uno formula over a period of about two years so it was not a one-time experiment. My intention was to test about 20-25 films with BTZS, but due to unexpected circumstances had a change of plans in 2009-10 and have never gotten back to working with this formula, which is final as you find it on the Pyrocat web site at the end of the mixing instructions. My friend Sam Wang (http://www.samwang.us/) has used it for a lot of his development of B&W negatives since about 2009 and is very pleased with the results and simplicity of the formula. Grain is very fine and sharpness is exceptional, but as with all formulas acutance and grain are somewhat dependent on dilution and type of agitation. Pyro Uno is of course similar to Jay DeFehr's 510 formula, but as you mention is also quite different in that the synergy is pyrogallol + metol, not + phenidone.

Attached are three screen shots of "curve families" from my BTZS testing, from FP4, HP5 and Tmax100. Processing was with the 1+100 dilution, at 72F in BTZS tubes, with the tubes in constant motion in a water bath. When you look at each family of curves you will see that there are four pieces of information on each curve. The information is, from bottom to top, 1) time of development, 2) effective film speed, 3) Contrast Index, and 4) SBR (or subject brightness range as defined by Phil Davis). The differences in the family of curves you notice is more due to the film than the developer. You would see the same type of families with most traditional developers, both staining and non-staining.

Sandy

MDR
20-Feb-2014, 01:03
Thank you for the great info. Sam Wang liking the developer is a great plus.